Refrigerator

ABSTRACT

A refrigerator and an operating method thereof are disclosed. The refrigerator includes a refrigerator body having a storage chamber defined therein, a refrigeration cycle device for cooling the storage chamber, a thawing box mounted in the storage chamber, the thawing box having a plurality of air jet holes formed therethrough, a thawing heater mounted in the thawing box for heating a stored object in the thawing box, and a blower mounted at the thawing box for introducing cool air from the storage chamber into the thawing box through the air jet holes such that the stored object is cooled by the air and discharging the air out of the thawing box. The thawing box, the thawing heater, and the blower perform not only a thawing function but also a rapid cooling function, thereby manufacturing the refrigerator in a simple structure at low costs and improving spatial utilization of the storage chamber.

TECHNICAL FIELD

The present invention relates to a refrigerator and an operating method thereof, and more particularly to a refrigerator having a thawing unit for thawing a stored object and an operating method thereof.

BACKGROUND ART

Generally, a refrigerator is an apparatus that is capable of cooling a plurality of storage chambers, such as a refrigerating chamber and a freezing chamber, using a refrigeration cycle device including a compressor, a condenser, an expansion mechanism, and an evaporator.

In a case in which a refrigerator is provided with a rapid cooling chamber in addition to a simple cooling storage function with respect to a stored object, it is possible to rapidly cool the stored object. Also, in a case in which a thawing unit for thawing the stored object is mounted in a storage chamber, it is possible to easily thaw the stored object.

In conventional refrigerators, however, the rapid cooling chamber and the thawing unit are separately provided in each of the refrigerators, with the result that spatial utilization of each of the refrigerators is very low. In particular, when the stored object is thawed, protein at the surface of the stored object may denature due to overheating of the surface of the stored object, with the result that the quality of the stored object may be deteriorated.

DISCLOSURE Technical Problem

Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a refrigerator that is capable of minimizing deterioration in quality of a stored object due to thawing when the stored object is thawed.

It is another object of the present invention to provide a refrigerator that is capable of selectively performing a thawing function and a rapid cooling function using a single unit.

It is another object of the present invention to provide an operating method of a refrigerator that is capable of alternately repeating a heating operation using a thawing heater and a cooling operation using cool air.

Technical Solution

In accordance with one aspect of the present invention, the above and other objects can be accomplished by the provision of a refrigerator including a refrigerator body having a storage chamber defined therein, a refrigeration cycle device for cooling the storage chamber, a thawing box mounted in the storage chamber, the thawing box having a plurality of air jet holes formed therethrough, a thawing heater mounted in the thawing box for heating a stored object in the thawing box, and a blower mounted at the thawing box for introducing cool air from the storage chamber into the thawing box through the air jet holes such that the stored object is cooled by the air and discharging the air out of the thawing box.

The refrigerator may further include a manipulation unit for allowing a user to input a thawing mode and a controller for controlling the thawing heater and the blower according to the manipulation of the manipulation unit.

The refrigerator may further include a temperature sensor for measuring a temperature of the stored object, and

the controller may control the thawing heater to be turned off when the temperature sensed by the temperature sensor is equal to or greater than a heater off temperature, and may control the thawing heater to be turned on when the temperature sensed by the temperature sensor is equal to or less than a heater on temperature.

The controller may alternately control the thawing heater to be turned on/off and the blower to be turned on/off when a thawing mode is input through the manipulation unit.

The controller may alternately control the blower to be turned on and the thawing heater to be turned on/off when a thawing mode is input through the manipulation unit.

The controller may control the blower such that a rotation rate of the blower when the thawing heater is turned off is higher than a rotation rate of the blower when the thawing heater is turned on.

The controller may control the blower to be driven when a rapid cooling thawing mode is input through the manipulation unit.

The thawing box may include a box body, open at a front thereof, having a plurality of air jet holes formed through at least one selected from a group consisting of an upper side plate, a lower side plate, a left side plate, and a right side plate of the box body, and having a blower installation part formed at a rear side plate of the box body, and a thawing door for opening and closing the front of the box body, the thawing door being provided with a plurality of air jet holes.

The thawing box may further include a thawing shelf mounted in the box body such that the thawing shelf is spaced apart from the thawing heater, the thawing shelf being provided with a plurality of air jet holes.

In accordance with another aspect of the present invention, there is provided an operating method of a refrigerator including a thawing step of turning on a thawing heater mounted in a thawing box having a plurality of air jet holes formed therethrough to heat an interior of the thawing box when a thawing command is input and a chilling step of turning off the thawing heater upon completion of the thawing step and driving a blower mounted at the thawing box such that cool air in a storage chamber is supplied into the thawing box through the air jet holes.

The chilling step may be performed when a temperature of the storage object sensed during the execution of the thawing step is equal to or greater than a heater off temperature.

The chilling step may be completed when a temperature of the stored object sensed during the execution of the chilling step is equal to or less than a heater on temperature, and the blower may be stopped.

The thawing step and the chilling step may be repeated after the blower is stopped.

The thawing step and the chilling step may be alternately repeated for a predetermined thawing time.

In accordance with a further aspect of the present invention, there is provided an operating method of a refrigerator including a thawing step of driving a blower mounted in a thawing box having a plurality of air jet holes formed therethrough to spray cool air from a storage chamber into the thawing box and turning on a thawing heater mounted in the thawing box when a thawing command is input and a chilling step of turning off the thawing heater upon completion of the thawing step.

The blower may be driven at a first rotation rate at the thawing step, and the blower may be driven at a second rotation rate higher than the first rotation rate at the chilling step.

The chilling step may be performed when a temperature of the storage object sensed during the execution of the thawing step is equal to or greater than a heater off temperature.

The chilling step may be completed when a temperature of the stored object sensed during the execution of the chilling step is equal to or less than a heater on temperature, and the thawing step and the chilling step may be repeated.

The thawing step and the chilling step may be performed for a predetermined thawing time.

DESCRIPTION OF DRAWINGS

The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective view illustrating a refrigerator according to an embodiment of the present invention;

FIG. 2 is a schematic construction view of the refrigerator according to the embodiment of the present invention;

FIG. 3 is a sectional view of the refrigerator according to the embodiment of the present invention;

FIG. 4 is a partially enlarged sectional view illustrating a rapid cooling and thawing unit shown in FIGS. 1 to 3;

FIG. 5 is a flow chart illustrating an operating method of a refrigerator according to an embodiment of the present invention; and

FIG. 6 is a flow chart illustrating an operating method of a refrigerator according to another embodiment of the present invention.

BEST MODE

Now, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same or similar elements are denoted by the same reference numerals even though they are depicted in different drawings, and a detailed description thereof will be omitted.

FIG. 1 is a perspective view illustrating a refrigerator according to an embodiment of the present invention, FIG. 2 is a schematic construction view of the refrigerator according to the embodiment of the present invention, FIG. 3 is a sectional view of the refrigerator according to the embodiment of the present invention, and FIG. 4 is a partially enlarged sectional view illustrating a rapid cooling and thawing unit shown in FIGS. 1 to 3.

As shown in FIGS. 1 to 4, the refrigerator according to this embodiment includes a refrigerator body 2 having a storage chamber R defined therein, a refrigeration cycle device 10 for cooling the storage chamber R, and a rapid cooling and thawing unit 20 mounted in the storage chamber R for selectively rapidly cooling and thawing a stored object.

The refrigerator body 2 includes an outer case 3, an inner case 4 disposed inside the outer case 3, the inner case 4 defining storage chambers F and R, and doors 5 and 6 for opening and closing the storage chambers F and R, respectively.

A heat insulation material, such as foamed plastic, is disposed between the outer case 3 and the inner case 4 of the refrigerator body 2. Also, a heat insulation material, such as foamed plastic, is disposed in the doors 5 and 6.

A plurality of members constituting the inner case 4 are mounted in the refrigerator body 2 to define the storage chambers F and R. The doors 5 and 6 include a refrigerating chamber door 5 for opening and closing a refrigerating chamber R and a freezing chamber door 6 for opening and closing a freezing chamber F.

The refrigeration cycle device 10 includes a compressor 11 for compressing a refrigerant L, a condenser 12 for condensing the refrigerant L compressed by the compressor 11, an expander 13 for expanding the refrigerant L condensed by the condenser 12, and an evaporator 14 for evaporating the refrigerant L expanded by the expander 13 to cool the storage chambers F and R.

The compressor 11 compresses a low-temperature, low-pressure gas refrigerant L into a high-temperature, high-pressure gas refrigerant L. The compressor 11 is mounted in a machine room M defined in the refrigerator body 2 such that the machine room M is separated from the storage chambers F and R.

The condenser 12 is connected to the compressor 11 via a condenser inlet pipe. Also, the condenser 12 is connected to the expander 13 via a condenser outlet pipe. A refrigerant L, introduced from the compressor 11 via the condenser inlet pipe, is condensed by the condenser 12 while the refrigerant flows through the condenser 12, and is then discharged via the condenser outlet pipe.

The condenser 12 may be mounted at the rear of the refrigerator body 2 such that the condenser 12 is exposed to the outside. Alternatively, the condenser 12 may be mounted in the machine room M defined in the refrigerator body 2. In a case in which the condenser 12 is mounted in the machine room M, a condensing fan 15 for blowing air outside the refrigerator body 2 to the condenser 12 is mounted in the refrigerator body 2.

The expander 13 may be embodied by a capillary tube or an electronic expansion valve. The expander 13 expands the condensed refrigerant L discharged via the condenser outlet pipe.

The evaporator 14 is connected to the expander 13 via an evaporator inlet pipe. Also, the evaporator 14 is connected to the compressor 11 via an evaporator outlet pipe. A refrigerant L, introduced from the expander 13 via the evaporator inlet pipe, is expanded by the evaporator 14 while the refrigerant flows through the evaporator 14, is discharged via the evaporator outlet pipe, and flows to the compressor 11.

The evaporator 14 may be configured as a direct cooling type evaporator disposed at the outer walls of the storage chambers F and R in a contact manner to directly cool the storage chambers F and R. Alternatively, the evaporator 14 may be configured as an indirect cooling type evaporator for circulating air through the storage chambers F and R and the evaporator 14 for cooling the storage chambers F and R in a circulation manner. In a case in which the evaporator 14 is configured as the indirect cooling type evaporator, a circulation fan 16 for circulating air through the storage chambers F and R and the evaporator 14 is mounted in the refrigerator body 2.

When a user inputs a thawing mode, the rapid cooling and thawing unit 20 intermittently supplies heat to a stored object/interrupts the supply of heat to the stored object, and forcibly supplies cool air from the storage chamber R to the stored object while heat is not supplied to the stored object. On the other hand, when the user inputs a rapid cooling mode, the rapid cooling and thawing unit 20 forcibly supplies cool air from the storage chamber R to the stored object.

That is, in the thawing mode, the rapid cooling and thawing unit 20 supplies heat to the stored object such that the stored object is thawed. When heat is not supplied to the stored object, the rapid cooling and thawing unit 20 sprays cool air to the surface of the stored object such that protein at the surface of the stored object is prevented from denaturation. When the stored object is thawed/cool air is supplied to the stored object as described above, the surface temperature of the stored object is not excessively raised, and therefore, the quality of the stored object is improved. Also, in the rapid cooling mode, the rapid cooling and thawing unit 20 sprays cool air from the storage chamber R to the surface of the stored object to rapidly cool the stored object without supplying heat to the stored object.

When the user inputs the thawing mode, the rapid cooling and thawing unit 20 intermittently supplies heat to the stored object/interrupts the supply of heat to the stored object to thaw the stored object. On the other hand, when the user inputs the rapid cooling mode, the rapid cooling and thawing unit 20 forcibly supplies cool air from the storage chamber R to the stored object.

That is, the rapid cooling and thawing unit 20 selectively performs a thawing function and a rapid cooling function.

In the following description, the rapid cooling and thawing unit 20 intermittently supplies heat to the stored object/interrupts the supply of heat to the stored object, and forcibly supplies cool air from the storage chamber R to the stored object while heat is not supplied to the stored object in the thawing mode, in order to prevent the quality of the stored object from being deteriorated in the thawing mode, and the rapid cooling and thawing unit 20 forcibly supplies cool air from the storage chamber R to the stored object in the rapid cooling mode.

The rapid cooling and thawing unit 20 may be mounted in the freezing chamber F or the refrigerating chamber R. Preferably, the rapid cooling and thawing unit 20 is mounted in the refrigerating chamber R in order to prevent the temperature of the freezing chamber R from being abruptly increased due to heat generated during thawing and to prevent the stored object from being excessively cooled during rapid cooling.

The rapid cooling and thawing unit 20 may be mounted in the refrigerating chamber R. Alternatively, the rapid cooling and thawing unit 20 may be mounted in the refrigerating chamber door 5. In a case in which the rapid cooling and thawing unit 20 is mounted in the refrigerating chamber door 5, the front of the rapid cooling and thawing unit 20 may be opened and closed by an auxiliary door such that a stored object is placed in the rapid cooling and thawing unit 20, or the stored object is removed from the rapid cooling and thawing unit 20, without opening the refrigerating chamber door 5. An installation position of the auxiliary door is not particularly restricted.

The rapid cooling and thawing unit 20 includes a thawing box 30, a thawing heater 50, and a blower 60.

A stored object is placed in the thawing box 30 such that the stored object is thawed or rapidly cooled. The thawing box 30 is mounted in the refrigerating chamber R. The thawing box 30 is provided with a plurality of air jet holes 31 through which cool air is sprayed to the stored object.

The thawing box 30 includes a box body 38, open at the front thereof, having an upper side plate 32, a lower side plate 33, a left side plate 34, a right side plate 35, and a rear side plate 36, a thawing door 39 for opening and closing the front of the box body 38, and a thawing shelf 40 mounted in the box body 38 for allowing a stored object to be placed thereon.

The box body 38 has a plurality of air jet holes 31 a formed through at least one selected from a group consisting of the upper side plate 32, the lower side plate 33, the left side plate 34, the right side plate 35, and the rear side plate 36. Also, a blower installation part 37 is formed at one selected from a group consisting of the upper side plate 32, the lower side plate 33, the left side plate 34, the right side plate 35, and the rear side plate 36.

The thawing door 39 is provided with a plurality of air jet holes 31 b.

The thawing shelf 40 is mounted in the box body 38 such that the thawing shelf 40 is spaced apart from the thawing heater 50. Preferably, a plurality of thawing shelves 40 are mounted between the upper side plate 32 and the lower side plate 33 of the box body 38 such that the thawing shelves 40 are spaced apart from each other.

The thawing shelf 40 is provided with a plurality of air jet holes 31 c.

Preferably, the thawing box 30 is configured in a cool air suction and discharge structure in which, when the blower 60 is driven, cool air outside the thawing box 30 is suctioned into the thawing box 30 such that the cool air is sprayed to a stored object. In a case in which the rapid cooling and thawing unit 20 is mounted in the refrigerating chamber R, it is preferable to suction air from at least one selected from a group consisting of the front, the upper side, the lower side, the left side, and the right side of the thawing box 30 and discharge the suctioned air to the rear side of the thawing box 30, with the result that it is possible for the thawing box 30 to spray optimal cool air to the stored object. In the following description, air is suctioned from at least one selected from a group consisting of the front, the upper side, the lower side, the left side, and the right side of the thawing box 30, and the suctioned air is discharged to the rear side of the thawing box 30.

The air jet holes 31 a are formed through at least one selected from a group consisting of the upper side plate 32, the lower side plate 33, the left side plate 34, and the right side plate 35 of the box body 38. Also, the blower installation part 37 is formed at the rear side plate 36.

That is, when the blower 60 is driven, cool air in the refrigerating chamber R, in particular, cool air outside the thawing box 30 is suctioned through the front of the thawing box 30, and, in addition, is suctioned through at least one selected from a group consisting of the upper side, the lower side, the left side, and the right side of the thawing box 30. The suctioned air passes through the interior of the thawing box 30 and is discharged out of the thawing box 30 through the rear of the thawing box 30.

The thawing heater 50 is mounted in the thawing box 30 for heating the stored object in the thawing box 30.

The thawing heater 50 includes an upper thawing heater 52 mounted below the upper side plate 32 of the box body 38 and a lower thawing heater 54 mounted above the lower side plate 33 of the box body 38.

The upper thawing heater 52 is located between the upper side plate 32 of the box body 38 and the uppermost thawing shelf 40. The upper thawing heater 52 is mounted at the bottom of the upper side plate 32 of the box body 38.

The lower thawing heater 54 is located between the lower side plate 33 of the box body 38 and the lowermost thawing shelf 40. The lower thawing heater 54 is mounted at the top of the lower side plate 33 of the box body 38.

The blower 60 introduces cool air from the storage chamber into the thawing box 30 through the air jet holes 31 such that the stored object is cooled by the air, and discharges the air out of the thawing box 30. The blower 60 is mounted at the thawing box 30.

The blower 60 includes a housing 62 mounted at the blower installation part 37 formed at the box body 38, a fan 64 rotatably disposed in the housing 62, and a fan motor 66 mounted at the blower installation part 37 or in the housing 62 for rotating the fan 64.

It is possible for the blower 60 to blow air from the storage chamber R into the thawing box 30 such that the air is sprayed to the stored object in the thawing box 30. Alternatively, it is possible for the blower 60 to suction air from the thawing box 30 and discharge the suctioned air out of the thawing box 30.

The refrigerator according to this embodiment includes a manipulation unit 70 for allowing a user to input a thawing mode, a temperature sensor 80 for measuring the temperature of a stored object, and a controller 90 for controlling the thawing heater 50 and the blower 60 according to the manipulation of the manipulation unit 70.

The manipulation unit 70 is configured for a user to input desired temperatures of the storage chambers F and R and, in addition, to input a rapid cooling mode in addition the thawing mode.

The manipulation unit 70 may be embodied by a touch panel assembly including a liquid crystal display (LCD) panel and a touch screen mounted at the LCD panel. Alternatively, the manipulation unit 70 may include a plurality of button and switch sets in which each of the switches is switched by a corresponding one of the buttons.

The manipulation unit 70 includes a desired temperature manipulation unit for a user to input desired temperatures of the storage chambers F and R, a thawing mode manipulation unit for the user to input a thawing mode, and a rapid cooling manipulation unit for the user to input a rapid cooling mode.

The temperature sensor 80 may sense the temperature of a stored object in a direct contact manner or in a non-contact manner. In a case in which the temperature sensor 80 senses the temperature of the stored object in the direct contact manner, the temperature sensor 80 is mounted at the thawing shelf 40. On the other hand, in a case in which the temperature sensor 80 senses the temperature of the stored object in the non-contact manner, the temperature sensor 80 is mounted at one side of the box body 38.

In a case in which the temperature sensor 80 senses the temperature of the stored object in the non-contact manner, the temperature sensor 80 may be embodied by an infrared sensor.

When the temperature sensed by the temperature sensor 80 is equal to or greater than the heater off temperature, the controller 90 controls the thawing heater to be turned off. On the other hand, when the temperature sensed by the temperature sensor 80 is equal to or less than the heater on temperature, the controller 90 controls the thawing heater to be turned on.

Here, the heater off temperature is a temperature predetermined such that protein at the surface of the stored object is prevented from denaturation when the thawing heater 50 is turned on. The heater off temperature is set to be higher than the heater on temperature.

The heater on temperature is a temperature predetermined such that the surface temperature of the stored object is prevented from being lowered more than necessary.

When the thawing mode is input through the manipulation unit 70, the controller 90 may alternately control the thawing heater 50 to be turned on/off and the blower 60 to be driven/stopped.

That is, the blower 60 is stopped while the thawing heater 50 is operated, with the result that only heat generated from the thawing heater 50 is supplied to the stored object. When the thawing heater 50 is turned off, the blower 60 is driven to supply only cool air from the storage chamber R to the stored object. Subsequently, when the thawing heater 50 is turned on, the blower 60 is stopped, and the turning on/off of the thawing heater 50 and driving/stopping of the blower 60 are sequentially performed.

During the control as described above, the heat from the thawing heater 50 and the cool air from the storage chamber R are alternately supplied to the stored object. While the interior I of the stored object is gradually thawed, the temperature at the surface S of the stored object is repeatedly raised and lowered, with the result that the temperature at the surface S of the stored object is not raised more than necessary, and therefore, the stored object is uniformly thawed throughout the interior I and the surface S of the stored object.

When the thawing mode is input through the manipulation unit 70, the controller 90 may control the blower 60 to be continuously driven and control the thawing heater 50 to be turned on/off while the blower 60 is driven.

That is, when the blower 60 is driven, cool air from the storage chamber R is supplied into the thawing box 30. When the thawing heater 50 is turned on, the cool air in the thawing box 30 is heated by the thawing heater 50, with the result that the stored object is thawed. When the thawing heater 50 is turned off, the cool air in the thawing box 30 cools the stored object. When the interior I of the stored object is gradually thawed, the temperature at the surface S of the stored object is repeatedly raised and lowered, with the result that the temperature at the surface S of the stored object is not raised more than necessary, and therefore, the stored object is uniformly thawed throughout the interior I and the surface S of the stored object.

When the thawing mode is input through the manipulation unit 70, the controller 90 may control the blower 60 to be continuously driven, control the thawing heater 50 to be turned on/off while the blower 60 is driven, and control the blower 60 such that the rotation rate of the blower 60 when the thawing heater 50 is turned off is higher than the rotation rate of the blower 60 when the thawing heater 50 is turned on.

That is, when the thawing heater 50 is turned on, a small amount of cool air is supplied into the thawing box 30, with the result that heat from the thawing heater 50 is transmitted to the stored object by convection. When the thawing heater 50 is turned off, a large amount of cool air is supplied into the thawing box 30 to rapidly cool the stored object. Consequently, the stored object is rapidly thawed in a state in which the temperature at the surface S of the stored object is higher than when a large amount of cool air is supplied to the stored object irrespective of the thawing heater 50 being turned on/off.

When the rapid cooling mode is input through the manipulation unit 70, the controller 90 controls the blower 60 to be driven. When the rapid cooling mode is completed, the controller 90 controls the blower 60 to be stopped.

In the refrigerator according to this embodiment, the rapid cooling and thawing box 20 may selectively perform a thawing function and a rapid cooling function. In the rapid cooling mode, only the blower 60 is driven/stopped while the thawing heater 50 is not operated.

FIG. 5 is a flow chart illustrating an operating method of a refrigerator according to an embodiment of the present invention.

In the operating method of the refrigerator according to this embodiment, as shown in FIG. 5, a thawing step S1 and S2 and a chilling step S3 to S6 are sequentially performed in a thawing mode. The thawing step S1 and S2 and the chilling step S3 to S6 are repeated until the thawing mode is completed.

At the thawing step S1 and S2, when a user inputs a thawing command through the manipulation unit 70, the thawing heater 50 mounted in the thawing box 30 is turned on to heat the interior of the thawing box 30 having the air jet holes 31 formed therethrough.

When the thawing heater 50 is turned on, the thawing heater 50 emits heat. The heat is supplied to the surface S of a stored object, and is gradually transferred into the interior 1 of the stored object.

As the stored object is heated as described above, the stored object is gradually thawed, and the temperature at the surface S of the stored object is continuously raised.

The temperature sensor 80 senses the surface temperature of the stored object and outputs the sensed surface temperature of the stored object to the controller 90. When the sensed temperature reaches the heater off temperature, i.e., when the temperature of the stored object is equal to or greater than the heater off temperature, the controller 90 controls the thawing step S1 and S2 to be completed.

Also, the controller 90 controls the chilling step S3 to S6 to be performed such that the temperature at the surface S of the stored object is prevented from being excessively raised. That is, the chilling step S3 to S6 is performed when the temperature of the stored object sensed during the execution of the thawing step S1 and S2 is equal to or greater than the heater off temperature.

At the chilling step S3 to S6, the thawing heater 50 is turned off upon completion of the thawing step S1 and S2, and the blower 60 mounted in the thawing box 30 is driven such that cool air from the storage chamber R is supplied into the thawing box 30 through the air jet holes 31.

When the thawing heater 50 is turned off, the interior temperature of the thawing box 30 is not raised any more, and cool air from the storage chamber R is sprayed to the surface S of the stored object through the air jet holes 31.

The cool air sprayed to the surface S of the stored object cools the surface S of the stored object, with the result that protein at the surface S of the stored object is prevented from denaturation, the surface temperature of the stored object is gradually lowered, and the interior temperature of the thawing box 30 is gradually lowered.

When the temperature of the stored object sensed during the execution of the chilling step S3 to S6 is equal to or less than the heater on temperature, the chilling step S3 to S6 is completed. When the chilling step S3 to S6 is completed, the blower 60 is stopped.

The temperature sensor 80 senses the surface temperature of the stored object and outputs the sensed surface temperature of the stored object to the controller 90. When the sensed temperature reaches the heater on temperature, i.e., when the temperature of the stored object is equal to or less than the heater on temperature, the controller 90 controls the chilling step S3 to S6 to be completed.

Upon completion of the chilling step S3 to S6 as described above, the controller 90 compares time elapsed from the point of time when the thawing mode is commenced with a predetermined thawing time, which may be set by the user. When it is determined that the elapsed time has not reached the predetermined thawing time, the thawing step S1 and S2 and the chilling step S3 to S6 are repeated. When it is determined that the elapsed time has reached the predetermined thawing time, the thawing mode is completed.

That is, the thawing step S1 and S2 and the chilling step S3 to S6 are repeated for the predetermined thawing time. Consequently, the temperature at the surface S of the stored object is repeatedly raised and lowered, with the result that the temperature at the surface S of the stored object is not raised more than necessary, and therefore, the stored object is uniformly thawed throughout the interior I and the surface S of the stored object.

On the other hand, when the user inputs a rapid cooling mode, the controller 90 controls the blower 60 to be driven without the thawing heater 50 being turned on/off (S8 and S9).

When the blower 60 is driven, cool air from the storage chamber R is suctioned into the thawing box 30 and is then sprayed to the stored object to rapidly cool the stored object.

The controller 90 controls the blower 60 to be driven for a predetermined rapid cooling time, which may be set by the user. When it is determined that time elapsed from the point of time when the rapid cooling mode is commenced has reached the predetermined rapid cooling time, the blower 60 is stopped to complete the rapid cooling mode (S10 and S11).

FIG. 6 is a flow chart illustrating an operating method of a refrigerator according to another embodiment of the present invention.

In the operating method of the refrigerator according to this embodiment, as shown in FIG. 6, a thawing step S1′ and S2′ and a chilling step S3′ to S5′ are performed in a thawing mode. In a rapid cooling mode, a stored object is rapidly cooled. The operating method of the refrigerator according to this embodiment in the rapid cooling mode is identical to the operating method of the refrigerator according to the previous embodiment, and therefore, a detailed description thereof will not be given (S8′ to S11′).

In the operating method of the refrigerator according to this embodiment, the blower 60 is continuously driven at the thawing step S1′ and S2′ and at the chilling step S3′ to S5′. While the blower 60 is continuously driven, the thawing heater 50 is turned on, and is then turned off. The thawing heater 50 is repeatedly turned on/off until time elapsed from the point of time when the thawing mode is commenced reaches a predetermined thawing time. When it is determined that the elapsed time has reached the predetermined thawing time, the blower 60 is stopped.

In the operating method of the refrigerator according to this embodiment, the blower 60 may be driven at a uniform rotation rate at the thawing step S1′ and S2′ and at the chilling step S3′ to S5′. Alternatively, the rotation rate of the blower 60 may be changed depending upon the temperature of the stored object. In the following description, the rotation rate of the blower 60 is changed depending upon the temperature of the stored object.

At the thawing step S1′ and S2′, when a user inputs a thawing command through the manipulation unit 70, the thawing heater 50 mounted in the thawing box 30 is turned on to heat the interior of the thawing box 30 having the air jet holes 31 formed therethrough, and the blower 60 is driven.

At the thawing step S1′ and S2′, the blower 60 is driven at a first rotation rate. Here, the first rotation rate is set such that a small amount of cool air from the storage chamber R is supplied into the thawing box 30.

When the thawing heater 50 is turned on, the thawing heater 50 emits heat. The heat is supplied to the surface S of the stored object, and is gradually supplied into the interior I of the stored object. Also, cool air from the storage chamber R is supplied into the thawing box 30. The supplied air is heated by the thawing heater 50, and is then transmitted to the stored object by convection to assist the heating of the stored object.

As the stored object is heated as described above, the stored object is gradually thawed, and the temperature at the surface S of the stored object is continuously raised.

The temperature sensor 80 senses the surface temperature of the stored object and outputs the sensed surface temperature of the stored object to the controller 90. When the sensed temperature reaches the heater off temperature, i.e., when the temperature of the stored object is equal to or greater than the heater off temperature, the controller 90 controls the thawing step S1′ and S2′ to be completed.

Also, the controller 90 controls the chilling step S3′ to S5′ to be performed such that the temperature at the surface S of the stored object is prevented from being excessively raised. That is, the chilling step S3′ to S5′ is performed when temperature of the stored object sensed during the execution of the thawing step S1′ and S2′ is equal to or greater than the heater off temperature.

At the chilling step S3′ to S5′, the thawing heater 50 is turned off upon completion of the thawing step S1′ and S2′, and the blower 60 is continuously driven. At this time, the blower 60 is driven at a second rotation rate higher that the first rotation rate set at the thawing step S1′ and S2′.

When the thawing heater 50 is turned off, the interior temperature of the thawing box 30 is not raised any more, and a larger amount of cool air from the storage chamber R than the amount of the cool air at the thawing step S1′ and S2′ is suctioned into the thawing box 30, and is then sprayed to the stored object.

The cool air sprayed to the surface S of the stored object cools the surface S of the stored object, with the result that protein at the surface S of the stored object is prevented from denaturation, the surface temperature of the stored object is gradually lowered, and the interior temperature of the thawing box 30 is gradually lowered.

When the temperature of the stored object sensed during the execution of the chilling step S3′ to S5′ is equal to or less than the heater on temperature, the chilling step S3′ to S5′ is completed.

The temperature sensor 80 senses the surface temperature of the stored object and outputs the sensed surface temperature of the stored object to the controller 90. When the sensed temperature reaches the heater on temperature, i.e., when the temperature of the stored object is equal to or less than the heater on temperature, the controller 90 controls the chilling step S3′ to S5′ to be completed.

Upon completion of the chilling step S3′ to S5′ as described above, the controller 90 compares time elapsed from the point of time when the thawing mode is commenced with a predetermined thawing time, which may be set by the user. When it is determined that the elapsed time has not reached the predetermined thawing time, the thawing step S1′ and S2′ and the chilling step S3′ to S5′ are repeated. When it is determined that the elapsed time has reached the predetermined thawing time, the blower 60 is stopped, and the thawing mode is completed (S6′ and S7′).

That is, the thawing step S1′ and S2′ and the chilling step S3′ to S5′ are repeated for the predetermined thawing time. Consequently, the temperature at the surface S of the stored object is repeatedly raised and lowered, with the result that the temperature at the surface S of the stored object is not raised more than necessary, and therefore, the stored object is uniformly thawed throughout the interior I and the surface S of the stored object.

As apparent from the above description, the present invention with the above-stated construction has an effect in that cool air from the storage chamber is sprayed to the surface of the stored object heated by the thawing heater in the thawing mode, and therefore, it is possible to minimize deterioration in quality of the surface of the stored object.

Also, the present invention has an effect in that the thawing box, the thawing heater, and the blower perform not only a thawing function but also a rapid cooling function, and therefore, it is possible to manufacture the refrigerator in a simple structure at low costs and to improve spatial utilization of the storage chamber.

Also, the present invention has an effect in that cool air is rapidly sprayed to the stored object, and therefore, it is possible to rapidly lower the surface temperature of the stored object, to minimize a total thawing time, and to minimize a rapid cooling time.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. 

1. A refrigerator comprising: a refrigerator body having a storage chamber defined therein; a refrigeration cycle device for cooling the storage chamber; a thawing box mounted in the storage chamber, the thawing box having a plurality of air jet holes formed therethrough; a thawing heater mounted in the thawing box for heating a stored object in the thawing box; and a blower mounted at the thawing box for introducing cool air from the storage chamber into the thawing box through the air jet holes such that the stored object is cooled by the air and discharging the air out of the thawing box.
 2. The refrigerator according to claim 1, further comprising: a manipulation unit for allowing a user to input a thawing mode; and a controller for controlling the thawing heater and the blower according to the manipulation of the manipulation unit.
 3. The refrigerator according to claim 1, further comprising: a temperature sensor for measuring a temperature of the stored object, wherein the controller controls the thawing heater to be turned off when the temperature sensed by the temperature sensor is equal to or greater than a heater off temperature, and controls the thawing heater to be turned on when the temperature sensed by the temperature sensor is equal to or less than a heater on temperature.
 4. The refrigerator according to claim 1, wherein the controller alternately controls the thawing heater to be turned on/off and the blower to be turned on/off when a thawing mode is input through the manipulation unit.
 5. The refrigerator according to claim 1, wherein the controller alternately controls the blower to be turned on and the thawing heater to be turned on/off when a thawing mode is input through the manipulation unit.
 6. The refrigerator according to claim 5, wherein the controller controls the blower such that a rotation rate of the blower when the thawing heater is turned off is higher than a rotation rate of the blower when the thawing heater is turned on.
 7. The refrigerator according to claim 1, wherein the controller controls the blower to be driven when a rapid cooling thawing mode is input through the manipulation unit.
 8. The refrigerator according to claim 1, wherein the thawing box comprises: a box body, open at a front thereof, having a plurality of air jet holes formed through at least one selected from a group consisting of an upper side plate, a lower side plate, a left side plate, and a right side plate of the box body, and having a blower installation part formed at a rear side plate of the box body; and a thawing door for opening and closing the front of the box body, the thawing door being provided with a plurality of air jet holes.
 9. The refrigerator according to claim 8, wherein the thawing box further comprises a thawing shelf mounted in the box body such that the thawing shelf is spaced apart from the thawing heater, the thawing shelf being provided with a plurality of air jet holes.
 10. An operating method of a refrigerator, comprising: a thawing step of turning on a thawing heater mounted in a thawing box having a plurality of air jet holes formed therethrough to heat an interior of the thawing box when a thawing command is input; and a chilling step of turning off the thawing heater upon completion of the thawing step and driving a blower mounted at the thawing box such that cool air in a storage chamber is supplied into the thawing box through the air jet holes.
 11. The operating method according to claim 10, wherein the chilling step is performed when a temperature of the storage object sensed during the execution of the thawing step is equal to or greater than a heater off temperature.
 12. The operating method according to claim 11, wherein the chilling step is completed when a temperature of the stored object sensed during the execution of the chilling step is equal to or less than a heater on temperature, and the blower is stopped.
 13. The operating method according to claim 12, wherein the thawing step and the chilling step are repeated after the blower is stopped.
 14. The operating method according to claim 13, wherein the thawing step and the chilling step are alternately repeated for a predetermined thawing time.
 15. An operating method of a refrigerator, comprising: a thawing step of driving a blower mounted in a thawing box having a plurality of air jet holes formed therethrough to spray cool air from a storage chamber into the thawing box and turning on a thawing heater mounted in the thawing box when a thawing command is input; and a chilling step of turning off the thawing heater upon completion of the thawing step.
 16. The operating method according to claim 15, wherein the blower is driven at a first rotation rate at the thawing step, and the blower is driven at a second rotation rate higher than the first rotation rate at the chilling step.
 17. The operating method according to claim 15, wherein the chilling step is performed when a temperature of the storage object sensed during the execution of the thawing step is equal to or greater than a heater off temperature.
 18. The operating method according to claim 17, wherein the chilling step is completed when a temperature of the stored object sensed during the execution of the chilling step is equal to or less than a heater on temperature, and the thawing step and the chilling step are repeated.
 19. The operating method according to claim 18, wherein the thawing step and the chilling step are performed for a predetermined thawing time. 